Cards having a display using a heat reversible recording material are known where it is possible to repeatedly write the information. Such a card is referred to as "Rewrite Card". Usually, a rewrite layer is formed on a base material consisting of polyethylene, aluminum, etc. After a protecting layer is formed on the rewrite layer, the prescribed design will be printed in an area (hereafter referred to as "Non-Display") from which the display is removed. The card is made in the above method.
Such cards have a gap of several microns or so between a non-display section where the prescribed design is printed and a display section where the design is not printed. That is, the display is more concave than the non-display. For this reason, the contact of the thermal head is incomplete in the vicinity of the boundary (hereafter referred to as "Edge") between the two sections. As a result, a problem occurs in that a heat gradient is generated when information is written or erased in the display. That is, there was a problem in that the printing quality of the edge is low while the printing quality of the display is high in the vicinity of the center.
Also, when such cards reach the limits of the frequency in use of their displays, it is necessary to replace the cards themselves with new ones. Accordingly, the replacement poses a problem in that the economic burden becomes heavy.